<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<button type="button" id="b" >点击</button>
		<script>
			var count=0;
			var b=document.getElementById("b");
			b.onclick=function(){
				this.innerHTML="点击了这个按钮"+(++count)+"次";
			}
			b.onmouseover=function(){
				this.style.color="red";
			}
		</script>
	</body>
</html>